Low-water alarm



July 17, 1928. 1,677,830

G. W. KELLER LOW WATER ALARI Filed July 16, 1924 7 i ailzjyzapr, S511 I] I Patented July 17, 1928 1,677,830 PATENT, OFFICE.

GEORGE WILLIAM KELLER, or PORTSMOUTH, 01110.

LOW-WATER ALARM.

Application filed July 16,

This invention relates to an automatically controlled signaling device especially clesigned for automatically sounding a signal by admitting steam to a whistle when the steam pressure has reached a predetermined degree.

An important object of the invention is to provide a device of this character which may be readily and easily installed on a boiler eliminating the necessity of making extensive changes in the boiler construction to install the device.

With the foregoing and other objects in view which will appear as the description proceeds, the invention resides in the combination and arrangement of parts and in the details of construction hereinafter described and claimed, it being understood that changes in the precise embodiment of the invention herein disclosed, may be made within the scope of what is claimed, without departing from the spirit of the invention.

Referring to the drawing:

Figure 1 is a sectional view taken on line 11 of Figure 2.v

Figure 2 is a longitudinal sectional view through the device.

Referring to the drawing in detail, the device includes the tubular body portion 5 formed with enlargements 6 disposed at the ends thereof, the enlargements being provided with threaded portions to accommodate the caps 7. Positioned within the body portion is an expansible tubular member 8 which is shown as having its ends disposed between the enlargements 6 and the enlargements 9 of the caps 7.

Each cap 7 is formed with a threaded opening 10 that receives the nipples 11 which are of lengths to extend appreciable distances within the tubular member 8 as indicated at 12, the sections 12 being provided with openings to allow steam to pass outwardly therethrough.

Exhaust pipes 13 have threaded pipe sections 14 connected therewith through the elbows 15 and direct steam to the union 16 that also has connection with the pipe 17 that supports a steam whistle not shown. As clearly illustrated by Figure 1 of the drawing, the space between the tubular members 5 and 8 affords a passageway for the admission of steam thereto and since the tubular member 8 is provided with a cutout portion 18, communication between the pas- 1924. Serial No. 726,381.

sageway, and interior of the tubular member 8, is established, to admit steam to the interior of member 8.

Positioned within the tubular member 8 1s a valve member 19 formed with heads 20 disposed at its ends that are of diameters slightly less than the diameter of the tubular member 8 so that a steam-tight connection will be provided between the heads 20 and member 8 under normal conditions. The cut out portion 18 is disposed in such relation to the valve member 19, that it admits steam between the heads 20.

Thus it will be seen that when the water level in the boiler to which the device is attached becomes low, the heat will cause an expansion of the tubular member 8 creating a space between the tubular member and heads 20 allowing steam to pass from the tubular member to the nipples 11, from where it passes through the ipe 13 and to the whistle supporting pipe 1 and whistles, not shown, supported thereby, to the end that an alarm will be sounded indicating to an attendant that the water level within the boiler is low and should be replenished. The body portion 5 is formed with a lateral extension 21 adapted to accommodate one end of a drop pipe, which in the present showing is indicated at 22, which drop pipe permits the device to be positioned a predetermined distance from the crown sheet of the boiler.

Flanges 23 are formed on the extension 21 and are provided with openings to accommodate suitable bolts whereby the device may be secured in position on a boiler.

Directly opposite to the entrance end of the lateral extension 21, is a threaded opening 24 adapted to accommodate the threaded plug 25 that normally closes the same, it being understood that the plug 25 may be readily removed to facilitate the cleaning of the device. 7

I claim A low water signal for boilers including a tubular body portion closed at its end and provided with an inlet opening, an'expansible tubular member within the body portion and spaced therefrom, said member being closed at its ends and having a port intermediate its ends in open communication with said tubular body portion, a pipe connected at one end with said inlet opening and having its other end open and adapted to extend into the water space of a boiler below loo the normal Water level thereof, said pipe acting to conduct steam to said body portion upon a drop in Water level below said'open end, a spool-shaped valve disposed in sand tubular member having its heads positioned on opposite sides of said lateral port and normally in sealing engagement With the Walls of the expansible tubular member to close communication between said port and the ends of said tubular member, and pipe connections leading from the ends of said tubular member to direct steam to a signal when the expansible tube expands upon being subjected to steam.

In testimony that I claim the foregoing as my own, I have hereto affixed my signature.

GEORGE l/VILLIAM KELLER. 

